Certification of an Offshore CO2 Offloading and Injection Solution with Flexible Pipes

Abstract The increasing need for effective carbon capture and storage (CCS) solutions has driven the development of advanced technologies capable of facilitating large-scale CO? management. This paper explores the use of unbonded dynamic flexible pipes in combination with offshore direct CO? offloading systems, emphasizing their scalability and adaptability to transferring CO? from floating injection units. The focus is on presenting the development, qualification, and certification of these fully CO?-resistant flexible pipes, essential for cost-effective vessel-to-well CO? injection systems aimed at permanent geological storage. To address the challenges of CO? stress corrosion cracking (CO?-SCC) and other material failure modes, a new innovative corrosion- resistant material for high-pressure flexible pipes was developed. An extensive testing program was conducted to evaluate the material's performance under CO?-rich conditions. The successful results formed the basis for the certification of a CO?-resistant flexible pipe with a Technology Readiness Level of 5, which is now ready for commercial-scale deployment. Additionally, the paper explores the benefits of integrating flexible pipes with two CO2 offloading systems—Single Anchor Loading (SAL) and Submerged Turret Loading (STL)—known for their endurance, flexibility, and uptime, enabling continuous CO2 injection in all weather conditions. The corrosion-resistant flexible pipe, in combination with the CO2 offloading systems, is an example of two technologies leveraging the desired robustness and efficiency for CCS without the need for complex technology changes affecting the already established subsea infrastructure. Finally, the paper underscores the potential to reduce the time to first CO2 injection by utilizing proven technologies.